<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
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    <title>Document</title>
</head>
<body>
    <script>
        function generator(arr){
            var nextIndex=0;
            return {
                next:()=>{
                    if(nextIndex<arr.length){
                        return {value:arr[nextIndex++],done:false}
                    }else{
                        return {done:true}
                    }
                }
            }
        }
        var arr=["听歌","看电视","打游戏"];
        var obj=generator(arr);
        console.log(obj.next())
        console.log(obj.next())
        console.log(obj.next())
        console.log(obj.next())
       
    </script>
</body>
</html>